Effects Of Film Mulching And Different Nitrogen Application On Peanut Growth And Development In Guanzhong West Area

In order to explore the effects of plastic mulching and nitrogen levels on yield and water use efficiency of peanut in guanzhong area,the method of field experiment was adopted in the irrigation experimental station of northwest a&f university.Set the two ways of none coating with film(B)and coating with film(F),and combined with N0(0kg/hm~2),N1(60kg/hm~2),N2(120kg/hm~2),N3(180kg/hm~2),N4(240kg/hm~2),N5(300kg/hm~2)6 kinds of nitrogen levels.The above-ground dry matter accumulation,agronomic traits,yield,water consumption,and water use efficiency of peanuts under different filming conditions were studied.The following conclusions are drawn:(1)The effect of covering biodegradable film on moisture content of 0-100cm soil layer is related to growth period,nitrogen level and soil depth.At seedling stage,covered with plastic film can significantly improve the moisture content of 0-10cm soil layer,the rate of increase was12.4%to 33.6%under different nitrogen application levels,and with the increase of nitrogen application,the effect was weakened.But 10-20 cm soil layer,the water content of soil was increased only when N2 and N3 were applied,increased by 20.1%and 34.3%respectively.30-100cm soil layer,covered with plastic film was no significant effect on water content.At pod-pin stage,0-10cm soil layer,covered with plastic film could significantly increase17.6%and 29.1%under the conditions of N1 and N2,however,there was no obvious regular for other soil layers at other nitrogen application levels.At mature stage,mulching and nitrogen application had no significant effect on soil moisture content.The soil water storage was respectively increased by 12.5mm,14.5mm and 4.3mm at seedling stage,pod-pin stage and mature stage,the effects of different nitrogen application rates on soil water storage were always shown as follows:The lower the nitrogen level,the better the effect of soil water storage.(2)The effects of mulching and nitrogen application on the quality of ground dry matter were related to the growth period of peanut,the two factors present interaction.the pod bearing stage was the period when the stem dry weight of peanut was most affected by nitrogen application,nitrogen application can obviously increase stem dry weight,and the more nitrogen,the more significant increase,but at mature stage,stem dry weight increased first and then decreased with the increase of nitrogen application level,N1 and N2 levels increased stem dry weight,but N4 and N5 levels decreased by comparison N3 level.Nitrogen application levels N0,N1,N2,mulching film can increase the leaves dry weight of peanut in any growth period.Nitrogen application levels N3,N4,N5,The leaf growth of peanut was promoted by mulching in flower needle stage and pod bearig stage,but decrease leaf dry weight at mature stage.Leaf dry weight increased first and then decreased with the increase of nitrogen application level at pod bearing stage and mature stage.The same growth period,above-ground dry matter accumulation increased first and then decreased with the increase of nitrogen application level under the condition of covering with plastic film.Same nitrogen application level,mulching film can improve above-ground dry matter accumulation,it respectively increased by 20.2%to 27.3%,48.2%to 149.5%,7.3%to 43.3%at seedling stage,flower needle stage and pod bearing stage.At mature stage,mulching film increased the above-ground dry matter accumulation when nitrogen levels N0,N1,andN2,mulching film reduced the above-ground dry matter accumulation when nitrogen levels N3,N4 and N5.(3)The effects of mulching film and nitrogen application on photosynthetic rate and chlorophyll content were related to the growth period.At seedling stage,mulching film can increase chlorophyll content,increased by 1.2%-9.1%under the different nitrogen application levels,and chlorophyll content increased first and then decreased with the increase of nitrogen application level;At pod-pin stage,mulching film can significantly increase photosynthetic rate,respectively improve 14%,9%,89.7%,56.9%,11.9%,5.1%,especially N2 and N3 levels were significantly increased,the average is as high as 72.3%,mulching film can increase chlorophyll content,increased by 6.5%-23.4%under the different nitrogen application levels,and chlorophyll content increase first,decrease then increase with the increase of nitrogen application level,appear"double peak"situation.At podding period,the effects of different nitrogen application levels on photosynthetic rate were not obvious.meanwhile,whether or not the content of chlorophyll was increased by film mulching was related to the level of nitrogen application,mulching film can decrease chlorophyll content when nitrogen application level N0,N1,N5,mulching film can increase chlorophyll content when nitrogen application level N3,N4,and chlorophyll content increase first,decrease then increase with the increase of nitrogen application level,appear"double peak"situation.(4)Covered with plastic film can improve the yield and water use efficiency of peanut,the yield increase ranged from 17.3%to 24.8%,the water use efficiency of the peanuts could also be improved about 16.1%-22.9%under different nitrogen application rates.In addition,the peanut yield,water use efficiency,and nitrogen application rate showed a significant parabolic trend.When nitrogen application amount is less than 120kg/hm~2,increase nitrogen application can improve peanut yield and water use efficiency;When nitrogen application amount is more than 120kg/hm~2,increase nitrogen application can decrease peanut yield and water use efficiency.Under the conditions of this expertent,Nitrogen application amount of 120kg/hm~2 is an appropriate nitrogen application amount that can give consideration to both yield and water use efficiency,at which time the yield increase rate reaches 24.8%,water use efficiency improve22.9%.